In an LSI (Large Scale Integration) of a next generation or later, an extension diffusion layer with a depth shallower than 10 nm is required, and a new impurity doping technology and an ultra short time anneal technology are being developed at present so as to form such an extremely shallow diffusion layer.
Usually, in order to form a diffusion layer, after an impurity is doped in a semiconductor substrate, the semiconductor substrate is annealed. So as to form an extremely shallow diffusion layer using such a method, with respect to a doping technology a plasma doping and so on are noticed considering a three dimensional structure, and with respect to an anneal technology an ultra short time anneal such as a laser anneal, a flashlight anneal and so on are noticed.
But in such technologies, a process to dope an impurity and a process to anneal are performed by separate apparatuses for manufacturing a semiconductor device, which invites an increase in equipment investment cost. In addition, in the laser anneal and the flashlight anneal, as a surface of a semiconductor substrate is heated to a high temperature, a temperature difference is generated between the front surface and a rear surface of the semiconductor substrate, and the semiconductor substrate curves by heat stress, so that there is a possibility to generate a problem and so on that crystal defects such as crystal dislocation and so on generates in the semiconductor substrate.
In addition, with respect to another method to form a diffusion layer, there is a method where after an impurity layer is formed in a semiconductor substrate by an ion implantation and so on, a microwave is irradiated to the semiconductor substrate to anneal whole the semiconductor substrate. Such a method for manufacturing a semiconductor device is disclosed in Japanese Patent Application Publication No. 10-189473.
But in such a method for manufacturing a semiconductor device, in case that an extremely shallow diffusion layer with a depth of not more than 10 nm is formed, it is necessary to decrease sufficiently an acceleration voltage in ion implantation. When the acceleration voltage is low, a variation is generated in the distribution of the impurity in a depth direction, so that there is a possibility that the desired extremely shallow diffusion layer can not be formed. In addition, in the same manner as in the above-described laser anneal and so on, an apparatus for manufacturing a semiconductor device so as to dope an impurity and an apparatus for manufacturing a semiconductor device so as to anneal a semiconductor substrate are required separately, which invites an increase in equipment investment cost.